commune for living

Yes, it's possible, but it's a horrible commute by car (about an hour or more, each way in dense traffic) or the same by train. Personally I would think about moving.

Antwerp's a great place to live but quite a bit more expensive than Leuven.

Train

Give it a go and see how it works out. I have done Brussels-Antwerp by car before, and it very much depends on the street-to-street trip. The motorway bit in-between is relatively OK.

You might also want to get stuck into the job and see how it works out.

It'll depend on where you live in Leuven, and where you're trying to get to in Antwerp, but what route are you taking? It may be better to go via Aarschot, and then up the N10 to Antwerp.